In at least some computed tomograph (CT) imaging system configurations, an x-ray source projects a fan-shaped beam which is collimated to lie within an X-Y plane of a Cartesian coordinate system and generally referred to as the "imaging plane". The x-ray beam passes through the object being imaged, such as a patient. The beam, after being attenuated by the object, impinges upon an array of radiation detectors. The intensity of the attenuated beam radiation received at the detector array is dependent upon the attenuation of the x-ray beam by the object. Each detector element of the array produces a separate electrical signal that is a measurement of the beam attenuation at the detector location. The attenuation measurements from all the detectors are acquired separately to produce a transmission profile.
In known third generation CT systems, the x-ray source and the detector array are rotated with a gantry within the imaging plane and around the object to be imaged so that the angle at which the x-ray beam intersects the object constantly changes. X-ray sources typically include x-ray tubes, which emit the x-ray beam at a focal spot. X-ray detectors typically include a collimator for collimating x-ray beams received at the detector, a scintillator adjacent the collimator, and photodiodes adjacent the scintillator.
Multislice CT systems are used to obtain data for an increased number of slices during a scan. Known multislice systems typically include detectors generally known as 3-D detectors. With such 3-D detectors, a plurality of detector cells form separate channels arranged in columns and rows.
A scintillator for a 3-D detector may have scintillator elements with dimension of about 1.times.2.times.3 mm, with narrow gaps of only a few mils, for example, approximately 0.004 inches, between adjacent elements. As a result of the small size and the close proximity of the elements various problems arise. For example, a signal which impinges upon one scintillator element may be improperly reflected upward or to adjacent elements causing a loss of resolution.
Scintillators typically are cut using accurate dicing saws by-etching, or by laser cuting. Such cutting is necessary to provide the desired dimensions. The most common way to cut scintillators is with the outside diameter (OD) of a diamond saw. An OD saw has a diamond coating on the outside periphery of the blade to cut materials, such as ceramics. To maintain blade rigidity for accurate cuts, very high speeds are used, e.g., from 10,000 to 30,000 rpm. Cutting gaps, for example, a 4 mil gap, in a ceramic scintillator, however can be difficult if the aspect ratio of the gap is greater than about 10. Particularly, OD saws often produce inaccurate cuts for scintillators with aspect ratios greater than 10. Additionally, if only one scintillator is cut at a time, many handling operations are required for each three dimensional array. These methods are time consuming and expensive.
It would be desirable to provide a method for increasing cutting accuracy of scintillators for a 3-D detector. It would also be desirable to provide such a method that minimizes the number of handling operations required to create the scintillators.